Railcar trucks are utilized at the undercarriage of railcars to support and provide the axles and wheels for the railcars. These railcar trucks or truck assemblies generally include a pair of parallel side frames and a bolster between these side frames. Each side frame has a generally centrally positioned portal outlined by a forward column surface, a rearward column surface, a base and a roof portion. The bolster has a first end and a second end, which ends generally have forward and rearward friction shoe pockets. Friction shoes, or snubbers, are operable to damp the oscillation, or frequency of the harmonic roll, of the railcar during its operation.
Within the above-noted portal spring-packs are nested with the bolster outer ends nested thereon for biasing of the bolster. In addition, the snubbers or friction shoes may be biased by a spring within the spring pack. There are various alternative arrangements and structures for biasing snubbers, which include constant and variable damping arrangements.
Friction shoes have a wearing or contacting face for engagement with a side-frame column surface. However, this friction shoe engagement involves metal to metal contact, which involves a wearing condition between the surfaces and potential galling or gouging of one or both surfaces. Metal-to-metal contact usually results in significant wear on the softer material, which in this circumstance may be the column surface . As repair of the column surface or replacement of the side frame are undesirable, difficult and expensive propositions wear plates are frequently mounted on the column surfaces. These wear plates are generally rectangular segment, which are hard or hardened material. The segments are mounted directly on the column surfaces for wearing contact with the snubbers or friction shoes to minimize wear on the side frame columns. As the frictions shoes are smaller segments and subject to wear, they are considered to be more easily replaced.
The mounted wear plates are, as noted, usually rectangular segments, which can potentially gouge or mar the bolster lands adjacent to the friction shoe and friction shoe pocket. Therefore, the present invention provides corner relief, or broken corners, to provide clearance between the wear plate and the bolster lands, while simultaneously providing a wearing surface for the friction shoe.